title: Apolipoprotein A-II polymorphism: relationships to behavioural and hormonal mediators of obesity.
abstract: BACKGROUND
  The interaction between apolipoprotein A-II (APOA2) m265 genotype and saturated fat for obesity traits has been more extensively demonstrated than for any other locus, but behavioural and hormonal mechanisms underlying this relationship are unexplored. In this study, we evaluated relationships between APOA2 and obesity risk with particular focus on patterns of eating and ghrelin, a hormonal regulator of food intake.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Overweight and obese subjects (n=1225) were evaluated at baseline in five weight loss clinics in southeastern Spain.
  
  
  METHODS
  Behavioural data were assessed using a checklist of weight loss obstacles. Logistic regression models were fitted to estimate the risk of a specific behaviour associated with APOA2 genotype. Relationships between APOA2 genotype and saturated fat intakes for anthropometric traits and plasma ghrelin were evaluated by analysis of variance. To construct categorical variables to evaluate interactions, saturated fat intake was dichotomized into high and low according to the population median intake or as tertiles.
  
  
  RESULTS
  Homozygous minor (CC) subjects were more likely to exhibit behaviours that impede weight loss ('Do you skip meals', odds ratio (OR)=2.09, P=0.008) and less likely to exhibit the protective behaviour of 'Do you plan meals in advance' (OR=0.64, P=0.034). Plasma ghrelin for CC subjects consuming low saturated fat was lower compared with (1) CC subjects consuming high saturated fat, (2) TT+TC carriers consuming low saturated fat and (3) TT+TC carriers consuming high saturated fat (all P<0.05).
  
  
  CONCLUSIONS
  APOA2 m265 genotype may be associated with eating behaviours and dietary modulation of plasma ghrelin. Expansion of knowledge of APOA2 and obesity to include modulation of specific behaviours and hormonal mediators not only broadens understanding of gene-diet interactions, but also facilitates the pragmatic, future goal of developing dietary guidelines based on genotype.
authors.affiliation: Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging, Tufts University School of Medicine, Boston, MA, USA.
authors.forename: C E
authors.initials: CE
authors.lastname: Smith
authors.forename: J M
authors.initials: JM
authors.lastname: Ordovás
authors.forename: C
authors.initials: C
authors.lastname: Sánchez-Moreno
authors.forename: Y-C
authors.initials: YC
authors.lastname: Lee
authors.forename: M
authors.initials: M
authors.lastname: Garaulet
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D016633:Apolipoprotein A-II / Q000235:genetics* / Q000378:metabolism; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D015930:Diet Records; D004041:Dietary Fats / Q000008:administration & dosage; D004435:Eating / Q000235:genetics*; D005247:Feeding Behavior / Q000523:psychology; D005260:Female; D005838:Genotype; D054439:Ghrelin / Q000097:blood*; D006801:Humans; D020738:Leptin / Q000097:blood; D016015:Logistic Models; D008297:Male; D009765:Obesity / Q000453:epidemiology / Q000235:genetics* / Q000523:psychology; D016017:Odds Ratio; D013030:Spain / Q000453:epidemiology; D061217:Weight Reduction Programs
chemical_list: D016633:Apolipoprotein A-II; D004041:Dietary Fats; D054439:Ghrelin; D020738:Leptin